Presently, there are many types of motor/generator available. The most common are:
i. DC motors or generators with or without permanent magnets PA1 ii . Synchronous motors or generators PA1 iii . Asynchronous motors or generators PA1 iv . Induction motors
More specifically, the present invention relates to electric motors and generators having an inverted stator/rotor configuration wherein the lamination core or cores and the coils wrapped thereabouts are fixed, with wires extending from coils extending axially from the frame, and rotors carry either permanent magnets or an array of self-exciting DC field poles having alternating polarities. Even more specifically, the present invention relates to electric motors or generators having the above mentioned stator/rotor configuration and having an integral heat sink, either air or liquid cooled, mounted proximate to the fixed coils and lamination cores.
Conventional DC motors or generators wherein the armature coils are wound on the rotor and the permanent magnets or field poles are mounted on the stator require brush type commutators. These brush type motors are gradually being replaced with more advanced brushless DC motors, AC synchronous motors or induction motors with variable frequency controls.
Whether acting as a generator or motor, these magnetic machines function because of relative motion between electrical conductors on a rotor or armature and a magnetic field. The magnetic field may be stationary and the electrical conductors revolve through it, or the electrical conductors may be stationary and the electrical field structure may revolve. It is also possible for both the conductors and the magnetic field to be in motion while the magnetic machine is functioning. When a generator is in function, the relative motion between the electrical conductors and the magnetic field produces an induced electromotive force, sometimes called an "EMF" or voltage, and an associated current in the active conductors. Generally, the EMF and current that are produced are alternating in direction and sometimes a "commutator" is used to make the electric current unidirectional in the external circuit of the magnetic machine. At any moment in time, these magnetic machines can only function as an electrical generator or an electrical motor.